Biomedical subjects

Yasuhiko Kitadai

Publications and source records attributed to Yasuhiko Kitadai.

75 records · Page 5Linked to original sources

PubMedDate not supplied

Frequent loss of heterozygosity on chromosome 10p15, a putative telomerase repressor/senescence gene locus, in gastric cancer.

Previous studies suggest that a telomerase repressor/senescence gene, which acts as a tumor suppressor gene, may be located on chromosome 10p15. However, there are no studies on alterations on chromosome 10p15 in gastric cancers. We, therefore, examined loss of heterozygosity (LOH) on the 10p15 in gastric cancers by microsatellite assay. Two microsatellite loci, D10S501 and D10S602, were used. Fifty-seven gastric cancers, including 36 intestinal type and 21 diffuse type, were selected. LOH at D10S602 and D10S501 was detected in 6 of 18 (33%) and 5 of 27 (19%) gastric cancers, respectively. There was no significant correlation between LOH at these loci and clinicopathologic features, including patient age, sex, tumor location, histologic subtype, depth of invasion, and lymph node metastasis. These data suggest that a putative telomerase repressor/senescence gene may be located on chromosome 10p15, especially at the D10S602, in gastric carcinogenesis, and that the putative gene malfunction may be involved in the early stages of gastric carcinogenesis.

Adult↗

PubMedDate not supplied

Somatic mutation in mitochondrial DNA and nuclear microsatellite instability in gastric cancer.

It was reported that somatic mutations in the mitochondrial DNA (mtDNA) are associated with high-frequency microsatellite instability (MSI-H) of the nuclear in gastric cancers. However, no correlation between mtDNA mutations and nuclear MSI-H was found in colorectal, breast, and renal cancers. Therefore, the association between mtDNA mutations and nuclear MSI-H in gastric cancers is controversial. We examined mtDNA mutations and nuclear MSI in a large panel of gastric cancers. One-hundred and five gastric cancers were selected. Mutations in the mononucleotide repeat (D310) of mtDNA and nuclear MSI at 5 microsatellite loci were examined by microsatellite assay. Somatic mutations in the mtDNA and nuclear MSI-H were detected in 16 (15%) and 14 (13%) of the gastric cancers, respectively. mtDNA mutations were detected in 2 of the 14 (14%) and 14 of the 91 (15%) tumors with and without nuclear MSI-H, respectively. There was no significant difference between them. These results suggest that somatic mutations in the mtDNA and nuclear MSI-H play important roles in gastric carcinogenesis, and that mtDNA mutations may not be associated with nuclear MSI-H in gastric cancers.

Adult↗

PubMedDate not supplied

Involvement of proinflammatory cytokines IL-1beta and IL-6 in progression of human gastric carcinoma.

UNLABELLED: Gastric carcinoma occurs in response to chronic inflammation of gastric mucosa infected with Helicobacter pylori. It is not known how cytokines affect the growth and progression of gastric carcinoma. MATERIALS AND METHODS: We measured tissue concentrations of the proinflammatory cytokines interleukin (IL)-1beta and IL-6 in gastric carcinoma and investigated the correlation between the levels of these cytokines and clinicopathological features. Biopsy specimens of tumors or adjacent normal mucosa were obtained from 42 Japanese patients with gastric carcinoma. Tissue levels of IL-1beta and IL-6 were measured by enzyme-linked immunosorbent assay. RESULTS: IL-1beta levels were significantly higher in the neoplasm than in the corresponding normal mucosa. The IL-6 levels in the neoplasm correlated significantly with the depth of invasion and lymphatic invasion. High levels of IL-1beta and IL-6 were characteristic of non-scirrhous type gastric carcinoma. CONCLUSION: These results suggest that IL-1beta and IL-6 are involved in the growth and progression of human gastric carcinoma.

Adult↗